Modern vehicles and other equipment are often equipped for remote entry control using a fob-type key device. A fob-type key device is a small, pocket-sized, radio-frequency (RF) signaling device, usually attached (like a fob) to the same key ring holding the mechanical ignition key (or other control key). By pressing a switch button on the fob-type key, the user is able to remotely open the door(s) and/or turn on a portion of the vehicle or other equipment without having to insert a mechanical key in a mechanical lock. This is a great convenience and an attractive safety feature. The fob-type keyless entry works by sending a coded RF signal to a receiver-decoder-actuator in the vehicle. This in-car system unlocks the door and/or performs other predetermined functions when it detects a valid “OPEN” code or equivalent on the RF signal received from the fob.
A disadvantage of such arrangement is that the fob-type key must be brought into the vicinity of the vehicle for it to function. Thus, the user must carry the fob-type key with him or her in order to be able to use it. Under these circumstances, the physical security of the fob-type key is essential for preventing unauthorized entry into the vehicle. If the fob is lost or stolen, vehicle security is compromised.
Sometimes vehicles are provided with key-less entry systems where the user only needs to remember a door code (e.g., a vehicle PIN number) and need not carry the electronic or mechanical key along. This eliminates the security risk arising from having to carry the key. Such key-less entry systems usually have the form of a small keypad built into the door of the car. To gain access to the vehicle, the user merely enters his or her personal entry code into the keypad and the door is automatically unlocked by the vehicle electronic system. A physical key or remote fob-type key is not needed. This arrangement is well known and very useful. However such keyless entry systems are still only in limited use and are usually available only as a hard-wired, “factory installed” option. “Factory installed” means that the components needed to provide the key-less entry function are hard-wired into the car at the time of construction and cannot be easily added afterward, for example, as a “dealer installed” or “after-market” option. This is a significant limitation.
Accordingly, it is desirable to be able to provide a keyless entry or activation system that is easily installed after a vehicle (or other equipment or structure) is manufactured and that does not depend on a factory installed keypad or keypad wiring harness. In addition, it is desirable that such an “after market” system be simple to install and operate, be of comparatively low cost and still have an appearance and function substantially equivalent to a factory installed system. Furthermore, other desirable features and characteristics of the present invention will become apparent from the subsequent detailed description and the appended claims, taken in conjunction with the accompanying drawings and the foregoing technical field and background.